In the US, there are also a lot of live in-person Free Events to learn Windows Phone 7 Development listed at http://www.msdnevents.com/wp7devlaunch. I encourage you to register now as they are filling up fast.

Jesse Liberty has also been creating a ton of new Windows Phone 7 training content (tutorials and videos) on Silverlight.net in preparation for the launch. Our MSDN Phone home (quit it with the ET jokes) hub has several introduction videos as well as links to other content.

In short, we're doing a ton to help you be successful with this new platform.